Time to check out the generator.

[ultrarunner]

Genset warmups have been discussed, but what about cool down? The manuals in several I've looked at recommend running the engine for 5 - 10 minutes with no load before shutting down. This is the manual page for the Kubota GL11000:

View attachment 1690916

I understand the need for a warmup period, but cool down? In any case, an automatic transfer switch takes neither into consideration.

As posted by several others, it may well be that the relatively low run time of a consumer grade genset is low enough to make these warm up and cool down cycles less important. However, IMO, it's the number of start-stop cycles that counts. The actual run time is irrelevant.

The number of recommended monthly, or quarterly, start-stop maintenance cycles will add up over time.

10 minute cool down while it monitors the stability of the circuit and if need be transfer back to carrying the load... Turbo Diesel.

Load monitoring for stability is a built in protection plus once load carried... even for a few seconds the generator keeps carrying for several minutes...

All 1995 tech and tier 0

 

[Up to the Axles]

The twin Cummins diesel powered generators in the basement of the building where I used to work, transfer from commercial to generator power in less than 5 seconds. What gives? Is there something magic about diesel engines used to power generators?

Many stationary plants are kept jacket-heated for rapid use. None more so than the backup power at a nuclear power plant; they are ready to accept loads in seconds.

Without them, you risk being the next Fukushima Daiichi.

 

[DarkBlack]

Many stationary plants are kept jacket-heated for rapid use. None more so than the backup power at a nuclear power plant; they are ready to accept loads in seconds.

Without them, you risk being the next Fukushima Daiichi.

The UPS generation I worked with took the load in milliseconds. Can’t get any faster than that

 

[ponytug]

The UPS generation I worked with took the load in milliseconds. Can’t get any faster than that

For critical loads, that's what I have always done. Enough UPS systems with the power and capacity to run the full load for ten minutes (aka as 20 min) to give the generators enough time to power up, warm up, and stabilize before the load was transferred. It helps the equipment under protection as they never lose power, and it can help the generator with the load transfer, especially if the UPS systems transfer at slightly different delay times.


All the best,

Peter

 

[DarkBlack]

For critical loads, that's what I have always done. Enough UPS systems with the power and capacity to run the full load for ten minutes (aka as 20 min) to give the generators enough time to power up, warm up, and stabilize before the load was transferred. It helps the equipment under protection as they never lose power, and it can help the generator with the load transfer, especially if the UPS systems transfer at slightly different delay times.


All the best,

Peter

I’m talking about a diesel generator UPS system, where the load never sees an interruption. No battery backup involved.

 

[5030]

. ? . Every generac standby, not portable, ive ever worked on has both. The control is not in the switch, its in the generator controls. Now,if the unit has been changed over to a 2 wire start, than all bets are off.

Both of mine do. The 21KW on Propane for the house and the 35KW JD Diesel unit that powers the shop and outbuildings. I believe (could be wrong as I don't pay a lot of attention to them) but I think 45 seconds before assuming the load and 2 minute cool down. Both are well over 15 years in service with zero issues (other than I had to replace the steel cab on the house unit because it was corroding away). It now has a new aluminum enclosure.

 

[bigtiller]

wouldn't we all like to have one of these?
It powers a cell phone tower in my field.

 

[Up to the Axles]

The UPS generation I worked with took the load in milliseconds. Can’t get any faster than that

100KW-1 MW UPSi are rather larger.

There are batteryless UPS's. I can't recall the name, but they are vertical shaft motor-generators with flywall mass. You could see them in datacenters. They run for 'n' seconds, enough of them for the Diesels to get up to speed.

 

[DarkBlack]

Very good. I’ve been waiting for someone to try to call me on the carpet for saying a diesel generator starts and carries the load in milliseconds.
Yes , a large 3ph 1,800 rpm motor/generator coupled to a huge flywheel. The moment a disturbance to a single sine wave on the line is detected, the computer instantly energizes the electric clutch to the diesel crankshaft , which is instantly ripped up to speed, and driving the load.
The building sees seemless power.
20 years. Average of almost daily starts. No warmup time. No engine rebuilds

 

[workinonit]

All power plants have very large UPS, battery banks and inverters. 125 VDC and 250 VDC battery banks. One for the emergency bus and one for the inverter. All of the nukes have backup generators for the critical aux equipment, usually in the megawatt range. Most NG and coal sites do not. They have the emergency bus so they can get the turbine offline and spun down without damage.

 

[ultrarunner]

For critical loads, that's what I have always done. Enough UPS systems with the power and capacity to run the full load for ten minutes (aka as 20 min) to give the generators enough time to power up, warm up, and stabilize before the load was transferred. It helps the equipment under protection as they never lose power, and it can help the generator with the load transfer, especially if the UPS systems transfer at slightly different delay times.


All the best,

Peter

I had to slow the transfer slightly to keep breakers from tripping.

Transferring motor loads in the 10 to 20hp size to quickly was the problem and the motors are required for air exchanges and to maintain positive room pressure for surgery.

 

[JasperFrank]

I like this thread as it makes me pay attention. Today was dedicated to starting and running every ICE, I have and checking fluids: 11 engines.
Two push Lawn Mowers
One Riding Mower
Motorcycle
Tractor
Generator
Chainsaw
Weed eater
Water pump
Two cars.
Took all day, but now I know it was done at least this year, and they all run.

 

[Blue Mule]

We lost power again for two days with air temps around 20F. It wasn't a crisis because I have a 3500 watt inverter generator that powers the 120v stuff in the house (fridge, lights, internet so we can work, etc.) and I have a kerosene heater that maintained a 65F temperature in the living room. But, if we had continued to be without power for a longer period of time it would have started to become a hassle.

This summer I'm going to get my fuse panel rewired to accept 240v input from a larger generator. Currently it's wired for 120v input and I do have a safety transfer switch. I want to get it swapped to accept 240v so that I can buy a larger generator and power the heat pump, water heater, and stove. That way we can take showers, keep the entire house at a levelized temp, and make food.

I have some questions:

Will 9500 watts be enough to run a 2.5 ton heat pump and a water heater?

Do I NEED to pay more for the inverter generators, or will the "standard" ones be fine?

When they change my transfer switch wiring to accept 240v input, will it automatically power everything in my fuse panel, or is this a one or the other situation? In other words, the 120v and 240v stuff will all work off the generator automatically?

 

[ultrarunner]

It will power everything up to the generator breaker limit.

I’ve powered all I needed but not at the same time because I’ve never owned a generator large enough to power all simultaneously…

 

[LouNY]

We lost power again for two days with air temps around 20F. It wasn't a crisis because I have a 3500 watt inverter generator that powers the 120v stuff in the house (fridge, lights, internet so we can work, etc.) and I have a kerosene heater that maintained a 65F temperature in the living room. But, if we had continued to be without power for a longer period of time it would have started to become a hassle.

This summer I'm going to get my fuse panel rewired to accept 240v input from a larger generator. Currently it's wired for 120v input and I do have a safety transfer switch. I want to get it swapped to accept 240v so that I can buy a larger generator and power the heat pump, water heater, and stove. That way we can take showers, keep the entire house at a levelized temp, and make food.

I have some questions:

Will 9500 watts be enough to run a 2.5 ton heat pump and a water heater?

Do I NEED to pay more for the inverter generators, or will the "standard" ones be fine?

When they change my transfer switch wiring to accept 240v input, will it automatically power everything in my fuse panel, or is this a one or the other situation? In other words, the 120v and 240v stuff will all work off the generator automatically?

It will be dependent on the transfer switch you have installed. The smaller stand alone switches only cover the loads wired into them.

Then this type which will allow all loads to be powered on a generator, they are available as manual as shown or as automatic transfer switches (ATS)

Here is a decent article on transfer switches;
Generators and Transfer Switches: A Comprehensive Guide

 

[ponytug]

We lost power again for two days with air temps around 20F. It wasn't a crisis because I have a 3500 watt inverter generator that powers the 120v stuff in the house (fridge, lights, internet so we can work, etc.) and I have a kerosene heater that maintained a 65F temperature in the living room. But, if we had continued to be without power for a longer period of time it would have started to become a hassle.

This summer I'm going to get my fuse panel rewired to accept 240v input from a larger generator. Currently it's wired for 120v input and I do have a safety transfer switch. I want to get it swapped to accept 240v so that I can buy a larger generator and power the heat pump, water heater, and stove. That way we can take showers, keep the entire house at a levelized temp, and make food.

I have some questions:

Will 9500 watts be enough to run a 2.5 ton heat pump and a water heater?

Do I NEED to pay more for the inverter generators, or will the "standard" ones be fine?

When they change my transfer switch wiring to accept 240v input, will it automatically power everything in my fuse panel, or is this a one or the other situation? In other words, the 120v and 240v stuff will all work off the generator automatically?

A larger transfer switch will enable a larger generator to power more. A 240V transfer switch should enable both 120 and 240V circuits.

A whole house transfer switch would enable the most support for keeping things backed up. (Usually 200A) Whole house generators often have options for their own automatic transfer switches.

The primary benefit to inverter generators is, I think, that they have an eco mode and can reduce their fuel consumption when demand is low. If you have a reasonably maintained, reasonable quality generator, the power should be good enough for most things. If the power quality isn't good enough for something, I think it is more practical to put those things that require "better/cleaner" power on an online UPS.

Types of UPS Systems | Eaton

There are three major types of Uninterruptible Power Supply (UPS) system. Before you buy, compare the features of each and select the types best suited for your needs.

tripplite.eaton.com

I always suggest that folks think about how long they might need power and then triple that number. Odds are that outages are going to get longer. That leads to how does one store enough fuel for the longer outage, and in the case of non-propane generators, how will does one keep the fuel fresh? Sometimes the available fuel dictates the generator and the generator fuel.

Whether 9,500W of claimed power is enough to run a 2.5T heat pump will depend both on what kind of heat pump it is and what the LRA and FLA is for the heat pump and your choice of generator.

All the best,

Peter

 

[Blue Mule]

Mine is an "interlock kit" style, similar to this:

Interlock Kit K-4010 for Siemens, ITE & Murray Panels

Kit-K- 4010 for Siemens ITE and Murray Panels

apelectric.com

I shut off the main breaker powering my 200 amp service fuse panel, then slide the plate blocking that switch, then flip the breaker for generator input. That's how my setup is isolated. So I guess the breaker they installed for the generator is what will determine how much input it will handle? I'll have to look when I get home and see what amp rating that one is.

 

[LouNY]

Mine is an "interlock kit" style, similar to this:

Interlock Kit K-4010 for Siemens, ITE & Murray Panels

Kit-K- 4010 for Siemens ITE and Murray Panels

apelectric.com

I shut off the main breaker powering my 200 amp service fuse panel, then slide the plate blocking that switch, then flip the breaker for generator input. That's how my setup is isolated. So I guess the breaker they installed for the generator is what will determine how much input it will handle? I'll have to look when I get home and see what amp rating that one is.

They are a decent very inexpensive way to go.

 

[ponytug]

Mine is an "interlock kit" style, similar to this:

Interlock Kit K-4010 for Siemens, ITE & Murray Panels

Kit-K- 4010 for Siemens ITE and Murray Panels

apelectric.com

I shut off the main breaker powering my 200 amp service fuse panel, then slide the plate blocking that switch, then flip the breaker for generator input. That's how my setup is isolated. So I guess the breaker they installed for the generator is what will determine how much input it will handle? I'll have to look when I get home and see what amp rating that one is.

Generally, the breaker is sized to the generator, and thus usually much less than the panel it is supporting. (E.g. 40-60A for a 200A panel) I think of the breaker getting sized to protect the generator.

@Blue Mule Like @LouNY, I think that they can be a simple and cost effective solution, but each panel takes its own particular interlock, and not all panels have interlocks available, and not all panels can have the generator breaker bolted down as is required in some AHJs. Bottom line: it may not work for your panel in your area, but it might.

All the best,

Peter

 

[bdhsfz6]

I test my generators monthly and use a similar interlock switch. I've been doing it for many years and each time I manually trip that 200A main breaker, it makes me wonder just how may duty cycles these main breakers are designed to handle.

Sure, they can be replaced if you can find one for an older breaker panel. Requires pulling the meter or working with live conductors though.